Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Sunrise and Sunset Differences
Name: Angel W.
Status: educator
Age: 30s
Location: N/A
Country: N/A
Date: 12/7/2004

Why does sunrise always looks so much different than the sunset?

I am not sure they do look different everywhere.

But one definite difference is:

- at sunset, your area has been warming all day
- at sunrise, your area has been cooling all night.

If you are on a coast with prevailing wind from the water, I suppose the cooler morning is more likely to be dulled by fog or clouds.

Do not forget that your personal impression of the appearance of the scene might depend a bit on whether you are experiencing warm or cold.

I think the top of the atmosphere swells upwards during the day and then subsides again each night, because at night the sun has stopped sizzling our beloved ozone and ionosphere with UV and solar particles.

On quiet nights perhaps there is a little less wind and turbulence near the ground, kicking up new dust.

Either of these might make it easier to see dark or deep blue night sky with stars on one side of you, and sunrise lighter blue sky on the other, at the same time. In comparison I tend to think the sunset sky leans towards whitish overhead and reddish horizon; if true that means more light-scattering and absorption is happening at sunset, and we can start to search for the proper reasons why.

I just realized: I am on the West coast. For me, sunrise is always over land, sunset over sea. Consider your own geography. It is likely to make some differences.

Jim Swenson

Click here to return to the Physics Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory